There is a substantial body of evidence supporting phototherapy for promoting human hair growth and regrowth. Additional evidence exists that low-level light therapy (LLLT) may be most beneficial if provided within one or more narrow spectral windows.
At least three US manufacturers sell products that deliver red light to the scalp: Sunetics, HairMax and Laser Hair Therapy. Prior art methods of dosing include “laser” combs using LEDs or laser diodes which must be slowly scanned across the scalp or full-head hoods similar in appearance and dimensions to the classic hair salon hair dryer hood which deliver red light to the head, usually in a doctor's office setting.
Conventional phototherapy regimens generally require the patient to administer the therapy, either by applying the light themselves, region by region with a light comb or by sitting under a hood in a medical or salon setting. There is a potential risk to the patients from the intense laser light leaking from an unconnected light source or from the housing into the patient's eyes.